Hypoglycemic effect of Cecropia obtusifolia Bertol aqueous extracts on type 2 diabetic patients.

Cecropia obtusifolia is widely used in Mexican traditional medicine due to its reputed hypoglycemic effect. During a period of 32 weeks, aqueous extracts of the leaves of this plant were administrated daily to 12 recently diagnosed type 2 diabetic patients, controlled only with diet and exercise. Serum glucose, cholesterol, triglyceride and insulin levels were determined every 15 days; HbA1c, ALT, AST and ALKP were measured every month. A significant reduction of glucose was detected after 4 weeks of administration but the reduction was significant and sustained after 18 weeks of administration. The HbA1c was also significantly reduced after 6 weeks of treatment. No significant changes on cholesterol, triglycerides ALT, AST, ALKP or insulin could be detected. No collateral effects were observed. After suspending the administration of the extract, and a follow-up of 34 weeks, the glucose and HbA1c levels increased reaching levels higher than the basal ones. It can be concluded that the aqueous extracts of Cecropia obtusifolia have a significant hypoglycemic effect with no adverse effects and that the mechanism of action is not brought about by stimulating the insulin secretion. The results support the fact that the extracts of Cecropia obtusifolia have a great potential to be further developed into a phytomedicine.

Los segmentos cardíacos primitivos, su implicación en la cardiogénesis normal aplicada a la cardiología pediátrica / Involvement of the primitive cardiac segments in the normal cardiogenesis. Its importance in the pediatric cardiology

The ample development of diagnostic echocardiography in pediatric cardiology has demanded precise knowledge of the abnormal anatomy of hearts that present congenital cardiac diseases. As a result, the information on morphologic and molecular aspects of cardiac embryogenesis has become fundamental to understand the anomalous anatomy of the malformed hearts. Based on these facts, in this paper we reviewed normal cardiogenesis, integrating the new information obtained experimentally in the chick embryo and from classic descriptive knowledge in humans. The age at which each cardiac segment appears is specified. At the same time, the changes in shape, relationships and position of these cardiac segments are detailed. Some implications of this process in the production of congenital cardiac defects and the importance of some specific genes are also discussed. This information is useful in the diagnosis of congenital cardiac diseases, as well as in discussing their embryogenesis. It is also beneficial in studying the possible mechanisms and genes implicated in normal morphogenesis of cardiac chambers, septa and valves. All this knowledge is important to plan strategies to avoid the production of this type of congenital pathologies.

Biotin supplementation reduces plasma triacylglycerol and VLDL in type 2 diabetic patients and in nondiabetic subjects with hypertriglyceridemia.

Biotin is a water-soluble vitamin that acts as a prosthetic group of carboxylases. Besides its role as carboxylase prosthetic group, biotin regulates gene expression and has a wide repertoire of effects on systemic processes. The vitamin regulates genes that are critical in the regulation of intermediary metabolism. Several studies have reported a relationship between biotin and blood lipids. In the present work we investigated the effect of biotin administration on the concentration of plasma lipids, as well as glucose and insulin in type 2 diabetic and nondiabetic subjects. Eighteen diabetic and 15 nondiabetic subjects aged 30-65 were randomized into two groups and received either 61.4 micromol/day of biotin or placebo for 28 days. Plasma samples obtained at baseline and after treatment were analyzed for total triglyceride, cholesterol, very low density lipoprotein (VLDL), glucose and insulin. We found that the vitamin significantly reduced (P=0.005) plasma triacylglycerol and VLDL concentrations. Biotin produced the following changes (mean of absolute differences between 0 and 28 day treatment+/-S.E.M.): a) triacylglycerol -0.55+/-0.2 in the diabetic group and -0.92+/-0.36 in the nondiabetic group; b) VLDL: -0.11+/-0.04 in the diabetic group and -0.18+/-0.07 in the nondiabetic group. Biotin treatment had no significant effects on cholesterol, glucose and insulin in either the diabetic or nondiabetic subjects. We conclude that pharmacological doses of biotin decrease hypertriglyceridemia. The triglyceride-lowering effect of biotin suggests that biotin could be used in the treatment of hypertriglyceridemia.

[Involvement of the primitive cardiac segments in the normal cardiogenesis. Its importance in the pediatric cardiology]. / Los segmentos cardíacos primitivos, su implicación en la cardiogénesis normal aplicada a la cardiología pediátrica.

The ample development of diagnostic echocardiography in pediatric cardiology has demanded precise knowledge of the abnormal anatomy of hearts that present congenital cardiac diseases. As a result, the information on morphologic and molecular aspects of cardiac embryogenesis has become fundamental to understand the anomalous anatomy of the malformed hearts. Based on these facts, in this paper we reviewed normal cardiogenesis, integrating the new information obtained experimentally in the chick embryo and from classic descriptive knowledge in humans. The age at which each cardiac segment appears is specified. At the same time, the changes in shape, relationships and position of these cardiac segments are detailed. Some implications of this process in the production of congenital cardiac defects and the importance of some specific genes are also discussed. This information is useful in the diagnosis of congenital cardiac diseases, as well as in discussing their embryogenesis. It is also beneficial in studying the possible mechanisms and genes implicated in normal morphogenesis of cardiac chambers, septa and valves. All this knowledge is important to plan strategies to avoid the production of this type of congenital pathologies.

[Effect of maternal diabetes on human and rat fetal development]. / Efecto de la diabetes materna en el desarrollo fetal de humanos y ratas.

Diabetes is a genetically determined metabolic disease with fasting hyperglycemia due to relative or absolute absence of insulin. With the use of exogenous insulin, successful gestations are now possible. Nevertheless, there are still severe problems associated, such as spontaneous abortion, perinatal mortality and congenital malformations. Caudal regression syndrome, disclosure of the neural tube and cardiovascular alterations are the most common malformations. Gestational diabetes can induce increased fetal corporal fat and macrosomia with hyperinsulinemia, hypoglycemic, hypoxia, metabolic acidosis and perinatal death. During adult life, diabetic mothers' children can develop obesity, glucose intolerance and type 2 diabetes. In order to study fetuses' alterations during diabetic gestations we now have animal models of diabetes. Maternal diabetes in rats alters fetal development in a very similar manner to that of humans. Although we do not accurately know the pathogenic mechanism by which diabetes produces fetuses' abnormal development, hyperglycemia and hyperketonemia had been mentioned to have predominant roles. Hyperglycemia damages DNA and increases oxidative stress and hyperketonemia increases the rate of embryo malformations. The addition of antioxidants such as C and E vitamins can reduce this damage. During adult life, diabetic rats' cubs have alterations in glucose metabolism and in reproductive function. The understanding of mechanisms by which maternal diabetes affects fetuses development, can help us to prevent complications and improve mothers' and children's life quality.

Efecto de la diabetes inducida sobre la reproducción y el desarrollo / Effect of induced diabetes upor reproduction and development

La diabetes mellitus es una enfermedad con una gran morbilidad y mortalidad, por lo que sus efectos se han estudiado en relación con los diversos órganos a los que afecta, sin ser la función reproductora la excepción. Para lograr esto, se ha recurrido a utilizar diversos animales como modelos experimentales, a los que se les induce diabetes. Se han descrito diversas sustancias para inducir la diabetes en animales, siendo la estretptozotocina (STZ) la que ha demostrado mayor eficacia. La STZ es un antibiótico producido por Streptomyces achromogenes, el cual tiene selectividad por las células beta del páncreas, destruyéndolas a través de la fragmentación del DNA. Se ha comprobado que la STZ diluida en amortiguador, estabilizada durante dos horas aproximadamente y almacenada a 6ºC, tiene una gran capacidad inductora de diabetes, sobre todo en especies como la rata, el ratón y el hamster. En ratas con diabetes inducida las alteraciones reproductivas se han asociado con alteraciones a nivel del eje hipotálamo-hipófisis-gónada, tanto por disminución de secreción de GnRH, como por deficiente secreción de LH, FSH y prolactina, así como por alteraciones a nivel gonadal y producción de hormonas esteroideas (testosterona, estrógenos y progesterona). Esto trae como consecuencia en ratas machos, la menor producción de espermatozoides, así la disminución en la movilidad de los mismos. En el caso de las hembras, las principales alteraciones son atrofia avárica, foliculogénesis anormal, insuficiencia del cuerpo lúteo, involución uterina y problemas asociados con el mantenimiento de la gestación. En diversos estudios se ha observado la prevalencia de malformaciones congénitas en los productos de ratas con diabetes inducida con STZ, siendo las más frecuetnes retraso en el desarrollo, alteraciones en el cierre del tubo neural, alteraciones cardiaca y micrognatias, entre otros